Rule 25, Fed.R.App.P., was amended effective December 1, 1996, to expound on the means by which papers may be filed and served. Amended subdivision (a) specifically provides for filing by First - Class Mail; but filing by equally expeditious classes of mail service and commercial carrier is also permitted. If a commercial carrier is used, the carrier must undertake to deliver the document in no more than three calendar days.

Subdivision (c) was amended to permit service by commercial carrier for delivery within 3 calendar days. In addition, when reasonable, service on a party is to be done in a manner at least as expeditious as the manner used to file the paper with the court. Under the amendment, service is complete upon delivery to the carrier.

Subdivision (d) was amended to require the certificate of service to state the date and manner by which the document was mailed or dispatched to the clerk.

Rule 25, N.D.R.App.P., allows filing and service by any class of mail. However, delivery by commercial carrier is probably not allowed. "Mail" means delivery conveyed under public authority. Prince v. Poulos, 876 F.2d 30, 32 n.1 (5th Cir. 1989). For example, Federal Express courier service is not "mail." Helmers v. Sortino, 545 N.W.2d 796, 799 (N.D. 1996). Should the 1996 federal amendment be followed? Should filing and service be allowed by commercial carrier?